System and method for detecting an obstruction

Abstract

A system for detecting an obstruction in the travel of a vent, such as a window glass in an opening of a vehicle, includes a reference element. The reference element is typically coded and either visible or invisible to the naked eye or emits a light signal which extends along at least a part of the perimeter of the opening. A detector, such as a matrix camera, detects the reference element at each point of at least a part of the perimeter of the opening. The system allows detection of an obstruction in the travel of the vent, regardless of variations in light or level of contrast, improving the quality of the detection.

1 . A system for detecting an obstruction in a path of travel of a vent in an opening of a vehicle comprising: 
 a reference element which extends over at least a part of a perimeter of the opening; and    a detector which detects the reference element at each point of the at least a part of the perimeter of the opening.    
     
     
         2 . The system according to  claim 1 , wherein the reference element is a coded segment.  
     
     
         3 . The system according to  claim 2 , wherein the coded segment is invisible to the naked eye.  
     
     
         4 . The system according to  claim 2 , wherein the coded segment is space coded.  
     
     
         5 . The system according to  claim 4 , wherein the coded segment is achieved by differentiating between one of a color, a type of surface and a shape of the coded segment.  
     
     
         6 . The system according to  claim 1 , further including a light source which is either visible or invisible and frequency-coded or time-coded to illuminate the perimeter of the opening.  
     
     
         7 . The system according to  claim 1 , wherein the reference element is a segment emitting a light signal detected by the detector.  
     
     
         8 . The system according to  claim 7 , wherein the light signal emitted by the reference element is time-coded or frequency-coded.  
     
     
         9 . The system according to  claim 1 , wherein the reference element extends over at least 50 mm of the perimeter of the opening.  
     
     
         10 . The system according to  claim 1 , wherein the detector is a matrix camera with a matrix of at least 8×8 pixels.  
     
     
         11 . The system according to  claim 1 , wherein the reference element is one of created in a trim of the perimeter of the opening, mounted on the trim of the perimeter of the opening, created on the vent, mounted on the vent, created on another trim of the vent and mounted on the another trim of the vent.  
     
     
         12 . The system according to  claim 1 , wherein the detector detects the reference element almost simultaneously at each point of an area to be protected which includes the at least a part of the perimeter, and one point corresponds to a unit of at least 0.5 mm long along the perimeter.  
     
     
         13 . The system according to  claim 1  further including a filter that modifies a distribution of light rays emitted by a light source or modifies an intensity of the light rays received by the detector.  
     
     
         14 . The system according to  claim 13 , wherein the reference element is one of created in a trim of the perimeter of the opening, mounted on the trim of the perimeter of the opening, created on the vent, mounted on the vent, created on another trim of the vent and mounted on the another trim of the vent.  
     
     
         15 . The system according to  claim 14 , wherein the detector is a matrix camera and the filter is a lens coupled to the matrix camera, and each point of the perimeter corresponds substantially to an equal number of pixels of the matrix camera.  
     
     
         16 . A method for detecting an obstruction in a path of travel of a vent in an opening, the method comprising the steps of: 
 detecting a reference element at each point of an area to be protected with a detector, wherein the reference element is on a part of a perimeter of an opening that corresponds to the area to be protected; and    detecting an obstruction when the detector does not detect the reference element at each point of the area to be protected.    
     
     
         17 . The method according to  claim 15 , wherein the step of detecting the reference element by the detector occurs almost simultaneously at each point of the area to be protected, wherein the area includes at least the part of the perimeter of the opening.